#include "dna.h"
#include <bits/stdc++.h>
using namespace std;
const int maxn = 100005;
int n;
int prefa1[maxn], prefa2[maxn];
int prefc1[maxn], prefc2[maxn];
int preft1[maxn], preft2[maxn];
int prefac[maxn], prefat[maxn], prefca[maxn], prefct[maxn], prefta[maxn], preftc[maxn];
void init(string a, string b)
{
n = a.size();
a = "#" + a;
b = "#" + b;
for (int i = 1; i <= n; ++i)
{
prefa1[i] = prefa1[i - 1];
prefa2[i] = prefa2[i - 1];
prefc1[i] = prefc1[i - 1];
prefc2[i] = prefc2[i - 1];
preft1[i] = preft1[i - 1];
preft2[i] = preft2[i - 1];
prefac[i] = prefac[i - 1];
prefat[i] = prefat[i - 1];
prefca[i] = prefca[i - 1];
prefct[i] = prefct[i - 1];
prefta[i] = prefta[i - 1];
preftc[i] = preftc[i - 1];
if (a[i] == 'A') ++prefa1[i];
else if (a[i] == 'C') ++prefc1[i];
else if (a[i] == 'T') ++preft1[i];
if (b[i] == 'A') ++prefa2[i];
else if (b[i] == 'C') ++prefc2[i];
else if (b[i] == 'T') ++preft2[i];
if (a[i] == 'A' && b[i] == 'C') ++prefac[i];
else if (a[i] == 'A' && b[i] == 'T') ++prefat[i];
else if (a[i] == 'C' && b[i] == 'A') ++prefca[i];
else if (a[i] == 'C' && b[i] == 'T') ++prefct[i];
else if (a[i] == 'T' && b[i] == 'A') ++prefta[i];
else if (a[i] == 'T' && b[i] == 'C') ++preftc[i];
}
}
int get_distance(int x, int y)
{
++x;
++y;
if (prefa1[y] - prefa1[x - 1] != prefa2[y] - prefa2[x - 1]) return -1;
if (prefc1[y] - prefc1[x - 1] != prefc2[y] - prefc2[x - 1]) return -1;
if (preft1[y] - preft1[x - 1] != preft2[y] - preft2[x - 1]) return -1;
int ans = 0;
ans += min(prefac[y] - prefac[x - 1], prefca[y] - prefca[x - 1]);
ans += max(prefat[y] - prefat[x - 1], prefta[y] - prefta[x - 1]);
ans += max(prefct[y] - prefct[x - 1], preftc[y] - preftc[x - 1]);
return ans;
}
